s390/3215: free memory in error path
[cascardo/linux.git] / drivers / s390 / char / con3215.c
1 /*
2  * 3215 line mode terminal driver.
3  *
4  * Copyright IBM Corp. 1999, 2009
5  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
6  *
7  * Updated:
8  *  Aug-2000: Added tab support
9  *            Dan Morrison, IBM Corporation <dmorriso@cse.buffalo.edu>
10  */
11
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kdev_t.h>
15 #include <linux/tty.h>
16 #include <linux/tty_flip.h>
17 #include <linux/vt_kern.h>
18 #include <linux/init.h>
19 #include <linux/console.h>
20 #include <linux/interrupt.h>
21 #include <linux/err.h>
22 #include <linux/reboot.h>
23 #include <linux/serial.h> /* ASYNC_* flags */
24 #include <linux/slab.h>
25 #include <asm/ccwdev.h>
26 #include <asm/cio.h>
27 #include <asm/io.h>
28 #include <asm/ebcdic.h>
29 #include <asm/uaccess.h>
30 #include <asm/delay.h>
31 #include <asm/cpcmd.h>
32 #include <asm/setup.h>
33
34 #include "ctrlchar.h"
35
36 #define NR_3215             1
37 #define NR_3215_REQ         (4*NR_3215)
38 #define RAW3215_BUFFER_SIZE 65536     /* output buffer size */
39 #define RAW3215_INBUF_SIZE  256       /* input buffer size */
40 #define RAW3215_MIN_SPACE   128       /* minimum free space for wakeup */
41 #define RAW3215_MIN_WRITE   1024      /* min. length for immediate output */
42 #define RAW3215_MAX_BYTES   3968      /* max. bytes to write with one ssch */
43 #define RAW3215_MAX_NEWLINE 50        /* max. lines to write with one ssch */
44 #define RAW3215_NR_CCWS     3
45 #define RAW3215_TIMEOUT     HZ/10     /* time for delayed output */
46
47 #define RAW3215_FIXED       1         /* 3215 console device is not be freed */
48 #define RAW3215_WORKING     4         /* set if a request is being worked on */
49 #define RAW3215_THROTTLED   8         /* set if reading is disabled */
50 #define RAW3215_STOPPED     16        /* set if writing is disabled */
51 #define RAW3215_TIMER_RUNS  64        /* set if the output delay timer is on */
52 #define RAW3215_FLUSHING    128       /* set to flush buffer (no delay) */
53
54 #define TAB_STOP_SIZE       8         /* tab stop size */
55
56 /*
57  * Request types for a 3215 device
58  */
59 enum raw3215_type {
60         RAW3215_FREE, RAW3215_READ, RAW3215_WRITE
61 };
62
63 /*
64  * Request structure for a 3215 device
65  */
66 struct raw3215_req {
67         enum raw3215_type type;       /* type of the request */
68         int start, len;               /* start index & len in output buffer */
69         int delayable;                /* indication to wait for more data */
70         int residual;                 /* residual count for read request */
71         struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */
72         struct raw3215_info *info;    /* pointer to main structure */
73         struct raw3215_req *next;     /* pointer to next request */
74 } __attribute__ ((aligned(8)));
75
76 struct raw3215_info {
77         struct tty_port port;
78         struct ccw_device *cdev;      /* device for tty driver */
79         spinlock_t *lock;             /* pointer to irq lock */
80         int flags;                    /* state flags */
81         char *buffer;                 /* pointer to output buffer */
82         char *inbuf;                  /* pointer to input buffer */
83         int head;                     /* first free byte in output buffer */
84         int count;                    /* number of bytes in output buffer */
85         int written;                  /* number of bytes in write requests */
86         struct raw3215_req *queued_read; /* pointer to queued read requests */
87         struct raw3215_req *queued_write;/* pointer to queued write requests */
88         struct tasklet_struct tlet;   /* tasklet to invoke tty_wakeup */
89         wait_queue_head_t empty_wait; /* wait queue for flushing */
90         struct timer_list timer;      /* timer for delayed output */
91         int line_pos;                 /* position on the line (for tabs) */
92         char ubuffer[80];             /* copy_from_user buffer */
93 };
94
95 /* array of 3215 devices structures */
96 static struct raw3215_info *raw3215[NR_3215];
97 /* spinlock to protect the raw3215 array */
98 static DEFINE_SPINLOCK(raw3215_device_lock);
99 /* list of free request structures */
100 static struct raw3215_req *raw3215_freelist;
101 /* spinlock to protect free list */
102 static spinlock_t raw3215_freelist_lock;
103
104 static struct tty_driver *tty3215_driver;
105
106 /*
107  * Get a request structure from the free list
108  */
109 static inline struct raw3215_req *raw3215_alloc_req(void)
110 {
111         struct raw3215_req *req;
112         unsigned long flags;
113
114         spin_lock_irqsave(&raw3215_freelist_lock, flags);
115         req = raw3215_freelist;
116         raw3215_freelist = req->next;
117         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
118         return req;
119 }
120
121 /*
122  * Put a request structure back to the free list
123  */
124 static inline void raw3215_free_req(struct raw3215_req *req)
125 {
126         unsigned long flags;
127
128         if (req->type == RAW3215_FREE)
129                 return;         /* don't free a free request */
130         req->type = RAW3215_FREE;
131         spin_lock_irqsave(&raw3215_freelist_lock, flags);
132         req->next = raw3215_freelist;
133         raw3215_freelist = req;
134         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
135 }
136
137 /*
138  * Set up a read request that reads up to 160 byte from the 3215 device.
139  * If there is a queued read request it is used, but that shouldn't happen
140  * because a 3215 terminal won't accept a new read before the old one is
141  * completed.
142  */
143 static void raw3215_mk_read_req(struct raw3215_info *raw)
144 {
145         struct raw3215_req *req;
146         struct ccw1 *ccw;
147
148         /* there can only be ONE read request at a time */
149         req = raw->queued_read;
150         if (req == NULL) {
151                 /* no queued read request, use new req structure */
152                 req = raw3215_alloc_req();
153                 req->type = RAW3215_READ;
154                 req->info = raw;
155                 raw->queued_read = req;
156         }
157
158         ccw = req->ccws;
159         ccw->cmd_code = 0x0A; /* read inquiry */
160         ccw->flags = 0x20;    /* ignore incorrect length */
161         ccw->count = 160;
162         ccw->cda = (__u32) __pa(raw->inbuf);
163 }
164
165 /*
166  * Set up a write request with the information from the main structure.
167  * A ccw chain is created that writes as much as possible from the output
168  * buffer to the 3215 device. If a queued write exists it is replaced by
169  * the new, probably lengthened request.
170  */
171 static void raw3215_mk_write_req(struct raw3215_info *raw)
172 {
173         struct raw3215_req *req;
174         struct ccw1 *ccw;
175         int len, count, ix, lines;
176
177         if (raw->count <= raw->written)
178                 return;
179         /* check if there is a queued write request */
180         req = raw->queued_write;
181         if (req == NULL) {
182                 /* no queued write request, use new req structure */
183                 req = raw3215_alloc_req();
184                 req->type = RAW3215_WRITE;
185                 req->info = raw;
186                 raw->queued_write = req;
187         } else {
188                 raw->written -= req->len;
189         }
190
191         ccw = req->ccws;
192         req->start = (raw->head - raw->count + raw->written) &
193                      (RAW3215_BUFFER_SIZE - 1);
194         /*
195          * now we have to count newlines. We can at max accept
196          * RAW3215_MAX_NEWLINE newlines in a single ssch due to
197          * a restriction in VM
198          */
199         lines = 0;
200         ix = req->start;
201         while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) {
202                 if (raw->buffer[ix] == 0x15)
203                         lines++;
204                 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
205         }
206         len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
207         if (len > RAW3215_MAX_BYTES)
208                 len = RAW3215_MAX_BYTES;
209         req->len = len;
210         raw->written += len;
211
212         /* set the indication if we should try to enlarge this request */
213         req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE);
214
215         ix = req->start;
216         while (len > 0) {
217                 if (ccw > req->ccws)
218                         ccw[-1].flags |= 0x40; /* use command chaining */
219                 ccw->cmd_code = 0x01; /* write, auto carrier return */
220                 ccw->flags = 0x20;    /* ignore incorrect length ind.  */
221                 ccw->cda =
222                         (__u32) __pa(raw->buffer + ix);
223                 count = len;
224                 if (ix + count > RAW3215_BUFFER_SIZE)
225                         count = RAW3215_BUFFER_SIZE - ix;
226                 ccw->count = count;
227                 len -= count;
228                 ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1);
229                 ccw++;
230         }
231         /*
232          * Add a NOP to the channel program. 3215 devices are purely
233          * emulated and its much better to avoid the channel end
234          * interrupt in this case.
235          */
236         if (ccw > req->ccws)
237                 ccw[-1].flags |= 0x40; /* use command chaining */
238         ccw->cmd_code = 0x03; /* NOP */
239         ccw->flags = 0;
240         ccw->cda = 0;
241         ccw->count = 1;
242 }
243
244 /*
245  * Start a read or a write request
246  */
247 static void raw3215_start_io(struct raw3215_info *raw)
248 {
249         struct raw3215_req *req;
250         int res;
251
252         req = raw->queued_read;
253         if (req != NULL &&
254             !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) {
255                 /* dequeue request */
256                 raw->queued_read = NULL;
257                 res = ccw_device_start(raw->cdev, req->ccws,
258                                        (unsigned long) req, 0, 0);
259                 if (res != 0) {
260                         /* do_IO failed, put request back to queue */
261                         raw->queued_read = req;
262                 } else {
263                         raw->flags |= RAW3215_WORKING;
264                 }
265         }
266         req = raw->queued_write;
267         if (req != NULL &&
268             !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) {
269                 /* dequeue request */
270                 raw->queued_write = NULL;
271                 res = ccw_device_start(raw->cdev, req->ccws,
272                                        (unsigned long) req, 0, 0);
273                 if (res != 0) {
274                         /* do_IO failed, put request back to queue */
275                         raw->queued_write = req;
276                 } else {
277                         raw->flags |= RAW3215_WORKING;
278                 }
279         }
280 }
281
282 /*
283  * Function to start a delayed output after RAW3215_TIMEOUT seconds
284  */
285 static void raw3215_timeout(unsigned long __data)
286 {
287         struct raw3215_info *raw = (struct raw3215_info *) __data;
288         unsigned long flags;
289
290         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
291         raw->flags &= ~RAW3215_TIMER_RUNS;
292         if (!(raw->port.flags & ASYNC_SUSPENDED)) {
293                 raw3215_mk_write_req(raw);
294                 raw3215_start_io(raw);
295                 if ((raw->queued_read || raw->queued_write) &&
296                     !(raw->flags & RAW3215_WORKING) &&
297                     !(raw->flags & RAW3215_TIMER_RUNS)) {
298                         raw->timer.expires = RAW3215_TIMEOUT + jiffies;
299                         add_timer(&raw->timer);
300                         raw->flags |= RAW3215_TIMER_RUNS;
301                 }
302         }
303         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
304 }
305
306 /*
307  * Function to conditionally start an IO. A read is started immediately,
308  * a write is only started immediately if the flush flag is on or the
309  * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
310  * done immediately a timer is started with a delay of RAW3215_TIMEOUT.
311  */
312 static inline void raw3215_try_io(struct raw3215_info *raw)
313 {
314         if (!(raw->port.flags & ASYNC_INITIALIZED) ||
315                         (raw->port.flags & ASYNC_SUSPENDED))
316                 return;
317         if (raw->queued_read != NULL)
318                 raw3215_start_io(raw);
319         else if (raw->queued_write != NULL) {
320                 if ((raw->queued_write->delayable == 0) ||
321                     (raw->flags & RAW3215_FLUSHING)) {
322                         /* execute write requests bigger than minimum size */
323                         raw3215_start_io(raw);
324                 }
325         }
326         if ((raw->queued_read || raw->queued_write) &&
327             !(raw->flags & RAW3215_WORKING) &&
328             !(raw->flags & RAW3215_TIMER_RUNS)) {
329                 raw->timer.expires = RAW3215_TIMEOUT + jiffies;
330                 add_timer(&raw->timer);
331                 raw->flags |= RAW3215_TIMER_RUNS;
332         }
333 }
334
335 /*
336  * Call tty_wakeup from tasklet context
337  */
338 static void raw3215_wakeup(unsigned long data)
339 {
340         struct raw3215_info *raw = (struct raw3215_info *) data;
341         struct tty_struct *tty;
342
343         tty = tty_port_tty_get(&raw->port);
344         if (tty) {
345                 tty_wakeup(tty);
346                 tty_kref_put(tty);
347         }
348 }
349
350 /*
351  * Try to start the next IO and wake up processes waiting on the tty.
352  */
353 static void raw3215_next_io(struct raw3215_info *raw, struct tty_struct *tty)
354 {
355         raw3215_mk_write_req(raw);
356         raw3215_try_io(raw);
357         if (tty && RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE)
358                 tasklet_schedule(&raw->tlet);
359 }
360
361 /*
362  * Interrupt routine, called from common io layer
363  */
364 static void raw3215_irq(struct ccw_device *cdev, unsigned long intparm,
365                         struct irb *irb)
366 {
367         struct raw3215_info *raw;
368         struct raw3215_req *req;
369         struct tty_struct *tty;
370         int cstat, dstat;
371         int count;
372
373         raw = dev_get_drvdata(&cdev->dev);
374         req = (struct raw3215_req *) intparm;
375         tty = tty_port_tty_get(&raw->port);
376         cstat = irb->scsw.cmd.cstat;
377         dstat = irb->scsw.cmd.dstat;
378         if (cstat != 0)
379                 raw3215_next_io(raw, tty);
380         if (dstat & 0x01) { /* we got a unit exception */
381                 dstat &= ~0x01;  /* we can ignore it */
382         }
383         switch (dstat) {
384         case 0x80:
385                 if (cstat != 0)
386                         break;
387                 /* Attention interrupt, someone hit the enter key */
388                 raw3215_mk_read_req(raw);
389                 raw3215_next_io(raw, tty);
390                 break;
391         case 0x08:
392         case 0x0C:
393                 /* Channel end interrupt. */
394                 if ((raw = req->info) == NULL)
395                         goto put_tty;        /* That shouldn't happen ... */
396                 if (req->type == RAW3215_READ) {
397                         /* store residual count, then wait for device end */
398                         req->residual = irb->scsw.cmd.count;
399                 }
400                 if (dstat == 0x08)
401                         break;
402         case 0x04:
403                 /* Device end interrupt. */
404                 if ((raw = req->info) == NULL)
405                         goto put_tty;        /* That shouldn't happen ... */
406                 if (req->type == RAW3215_READ && tty != NULL) {
407                         unsigned int cchar;
408
409                         count = 160 - req->residual;
410                         EBCASC(raw->inbuf, count);
411                         cchar = ctrlchar_handle(raw->inbuf, count, tty);
412                         switch (cchar & CTRLCHAR_MASK) {
413                         case CTRLCHAR_SYSRQ:
414                                 break;
415
416                         case CTRLCHAR_CTRL:
417                                 tty_insert_flip_char(&raw->port, cchar,
418                                                 TTY_NORMAL);
419                                 tty_flip_buffer_push(&raw->port);
420                                 break;
421
422                         case CTRLCHAR_NONE:
423                                 if (count < 2 ||
424                                     (strncmp(raw->inbuf+count-2, "\252n", 2) &&
425                                      strncmp(raw->inbuf+count-2, "^n", 2)) ) {
426                                         /* add the auto \n */
427                                         raw->inbuf[count] = '\n';
428                                         count++;
429                                 } else
430                                         count -= 2;
431                                 tty_insert_flip_string(&raw->port, raw->inbuf,
432                                                 count);
433                                 tty_flip_buffer_push(&raw->port);
434                                 break;
435                         }
436                 } else if (req->type == RAW3215_WRITE) {
437                         raw->count -= req->len;
438                         raw->written -= req->len;
439                 }
440                 raw->flags &= ~RAW3215_WORKING;
441                 raw3215_free_req(req);
442                 /* check for empty wait */
443                 if (waitqueue_active(&raw->empty_wait) &&
444                     raw->queued_write == NULL &&
445                     raw->queued_read == NULL) {
446                         wake_up_interruptible(&raw->empty_wait);
447                 }
448                 raw3215_next_io(raw, tty);
449                 break;
450         default:
451                 /* Strange interrupt, I'll do my best to clean up */
452                 if (req != NULL && req->type != RAW3215_FREE) {
453                         if (req->type == RAW3215_WRITE) {
454                                 raw->count -= req->len;
455                                 raw->written -= req->len;
456                         }
457                         raw->flags &= ~RAW3215_WORKING;
458                         raw3215_free_req(req);
459                 }
460                 raw3215_next_io(raw, tty);
461         }
462 put_tty:
463         tty_kref_put(tty);
464 }
465
466 /*
467  * Drop the oldest line from the output buffer.
468  */
469 static void raw3215_drop_line(struct raw3215_info *raw)
470 {
471         int ix;
472         char ch;
473
474         BUG_ON(raw->written != 0);
475         ix = (raw->head - raw->count) & (RAW3215_BUFFER_SIZE - 1);
476         while (raw->count > 0) {
477                 ch = raw->buffer[ix];
478                 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
479                 raw->count--;
480                 if (ch == 0x15)
481                         break;
482         }
483         raw->head = ix;
484 }
485
486 /*
487  * Wait until length bytes are available int the output buffer.
488  * Has to be called with the s390irq lock held. Can be called
489  * disabled.
490  */
491 static void raw3215_make_room(struct raw3215_info *raw, unsigned int length)
492 {
493         while (RAW3215_BUFFER_SIZE - raw->count < length) {
494                 /* While console is frozen for suspend we have no other
495                  * choice but to drop message from the buffer to make
496                  * room for even more messages. */
497                 if (raw->port.flags & ASYNC_SUSPENDED) {
498                         raw3215_drop_line(raw);
499                         continue;
500                 }
501                 /* there might be a request pending */
502                 raw->flags |= RAW3215_FLUSHING;
503                 raw3215_mk_write_req(raw);
504                 raw3215_try_io(raw);
505                 raw->flags &= ~RAW3215_FLUSHING;
506 #ifdef CONFIG_TN3215_CONSOLE
507                 ccw_device_wait_idle(raw->cdev);
508 #endif
509                 /* Enough room freed up ? */
510                 if (RAW3215_BUFFER_SIZE - raw->count >= length)
511                         break;
512                 /* there might be another cpu waiting for the lock */
513                 spin_unlock(get_ccwdev_lock(raw->cdev));
514                 udelay(100);
515                 spin_lock(get_ccwdev_lock(raw->cdev));
516         }
517 }
518
519 /*
520  * String write routine for 3215 devices
521  */
522 static void raw3215_write(struct raw3215_info *raw, const char *str,
523                           unsigned int length)
524 {
525         unsigned long flags;
526         int c, count;
527
528         while (length > 0) {
529                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
530                 count = (length > RAW3215_BUFFER_SIZE) ?
531                                              RAW3215_BUFFER_SIZE : length;
532                 length -= count;
533
534                 raw3215_make_room(raw, count);
535
536                 /* copy string to output buffer and convert it to EBCDIC */
537                 while (1) {
538                         c = min_t(int, count,
539                                   min(RAW3215_BUFFER_SIZE - raw->count,
540                                       RAW3215_BUFFER_SIZE - raw->head));
541                         if (c <= 0)
542                                 break;
543                         memcpy(raw->buffer + raw->head, str, c);
544                         ASCEBC(raw->buffer + raw->head, c);
545                         raw->head = (raw->head + c) & (RAW3215_BUFFER_SIZE - 1);
546                         raw->count += c;
547                         raw->line_pos += c;
548                         str += c;
549                         count -= c;
550                 }
551                 if (!(raw->flags & RAW3215_WORKING)) {
552                         raw3215_mk_write_req(raw);
553                         /* start or queue request */
554                         raw3215_try_io(raw);
555                 }
556                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
557         }
558 }
559
560 /*
561  * Put character routine for 3215 devices
562  */
563 static void raw3215_putchar(struct raw3215_info *raw, unsigned char ch)
564 {
565         unsigned long flags;
566         unsigned int length, i;
567
568         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
569         if (ch == '\t') {
570                 length = TAB_STOP_SIZE - (raw->line_pos%TAB_STOP_SIZE);
571                 raw->line_pos += length;
572                 ch = ' ';
573         } else if (ch == '\n') {
574                 length = 1;
575                 raw->line_pos = 0;
576         } else {
577                 length = 1;
578                 raw->line_pos++;
579         }
580         raw3215_make_room(raw, length);
581
582         for (i = 0; i < length; i++) {
583                 raw->buffer[raw->head] = (char) _ascebc[(int) ch];
584                 raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
585                 raw->count++;
586         }
587         if (!(raw->flags & RAW3215_WORKING)) {
588                 raw3215_mk_write_req(raw);
589                 /* start or queue request */
590                 raw3215_try_io(raw);
591         }
592         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
593 }
594
595 /*
596  * Flush routine, it simply sets the flush flag and tries to start
597  * pending IO.
598  */
599 static void raw3215_flush_buffer(struct raw3215_info *raw)
600 {
601         unsigned long flags;
602
603         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
604         if (raw->count > 0) {
605                 raw->flags |= RAW3215_FLUSHING;
606                 raw3215_try_io(raw);
607                 raw->flags &= ~RAW3215_FLUSHING;
608         }
609         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
610 }
611
612 /*
613  * Fire up a 3215 device.
614  */
615 static int raw3215_startup(struct raw3215_info *raw)
616 {
617         unsigned long flags;
618
619         if (raw->port.flags & ASYNC_INITIALIZED)
620                 return 0;
621         raw->line_pos = 0;
622         raw->port.flags |= ASYNC_INITIALIZED;
623         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
624         raw3215_try_io(raw);
625         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
626
627         return 0;
628 }
629
630 /*
631  * Shutdown a 3215 device.
632  */
633 static void raw3215_shutdown(struct raw3215_info *raw)
634 {
635         DECLARE_WAITQUEUE(wait, current);
636         unsigned long flags;
637
638         if (!(raw->port.flags & ASYNC_INITIALIZED) ||
639             (raw->flags & RAW3215_FIXED))
640                 return;
641         /* Wait for outstanding requests, then free irq */
642         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
643         if ((raw->flags & RAW3215_WORKING) ||
644             raw->queued_write != NULL ||
645             raw->queued_read != NULL) {
646                 raw->port.flags |= ASYNC_CLOSING;
647                 add_wait_queue(&raw->empty_wait, &wait);
648                 set_current_state(TASK_INTERRUPTIBLE);
649                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
650                 schedule();
651                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
652                 remove_wait_queue(&raw->empty_wait, &wait);
653                 set_current_state(TASK_RUNNING);
654                 raw->port.flags &= ~(ASYNC_INITIALIZED | ASYNC_CLOSING);
655         }
656         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
657 }
658
659 static struct raw3215_info *raw3215_alloc_info(void)
660 {
661         struct raw3215_info *info;
662
663         info = kzalloc(sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA);
664         if (!info)
665                 return NULL;
666
667         info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA);
668         info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA);
669         if (!info->buffer || !info->inbuf) {
670                 kfree(info->inbuf);
671                 kfree(info->buffer);
672                 kfree(info);
673                 return NULL;
674         }
675
676         setup_timer(&info->timer, raw3215_timeout, (unsigned long)info);
677         init_waitqueue_head(&info->empty_wait);
678         tasklet_init(&info->tlet, raw3215_wakeup, (unsigned long)info);
679         tty_port_init(&info->port);
680
681         return info;
682 }
683
684 static void raw3215_free_info(struct raw3215_info *raw)
685 {
686         kfree(raw->inbuf);
687         kfree(raw->buffer);
688         tty_port_destroy(&raw->port);
689         kfree(raw);
690 }
691
692 static int raw3215_probe (struct ccw_device *cdev)
693 {
694         struct raw3215_info *raw;
695         int line;
696
697         /* Console is special. */
698         if (raw3215[0] && (raw3215[0] == dev_get_drvdata(&cdev->dev)))
699                 return 0;
700
701         raw = raw3215_alloc_info();
702         if (raw == NULL)
703                 return -ENOMEM;
704
705         raw->cdev = cdev;
706         dev_set_drvdata(&cdev->dev, raw);
707         cdev->handler = raw3215_irq;
708
709         spin_lock(&raw3215_device_lock);
710         for (line = 0; line < NR_3215; line++) {
711                 if (!raw3215[line]) {
712                         raw3215[line] = raw;
713                         break;
714                 }
715         }
716         spin_unlock(&raw3215_device_lock);
717         if (line == NR_3215) {
718                 raw3215_free_info(raw);
719                 return -ENODEV;
720         }
721
722         return 0;
723 }
724
725 static void raw3215_remove (struct ccw_device *cdev)
726 {
727         struct raw3215_info *raw;
728         unsigned int line;
729
730         ccw_device_set_offline(cdev);
731         raw = dev_get_drvdata(&cdev->dev);
732         if (raw) {
733                 spin_lock(&raw3215_device_lock);
734                 for (line = 0; line < NR_3215; line++)
735                         if (raw3215[line] == raw)
736                                 break;
737                 raw3215[line] = NULL;
738                 spin_unlock(&raw3215_device_lock);
739                 dev_set_drvdata(&cdev->dev, NULL);
740                 raw3215_free_info(raw);
741         }
742 }
743
744 static int raw3215_set_online (struct ccw_device *cdev)
745 {
746         struct raw3215_info *raw;
747
748         raw = dev_get_drvdata(&cdev->dev);
749         if (!raw)
750                 return -ENODEV;
751
752         return raw3215_startup(raw);
753 }
754
755 static int raw3215_set_offline (struct ccw_device *cdev)
756 {
757         struct raw3215_info *raw;
758
759         raw = dev_get_drvdata(&cdev->dev);
760         if (!raw)
761                 return -ENODEV;
762
763         raw3215_shutdown(raw);
764
765         return 0;
766 }
767
768 static int raw3215_pm_stop(struct ccw_device *cdev)
769 {
770         struct raw3215_info *raw;
771         unsigned long flags;
772
773         /* Empty the output buffer, then prevent new I/O. */
774         raw = dev_get_drvdata(&cdev->dev);
775         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
776         raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
777         raw->port.flags |= ASYNC_SUSPENDED;
778         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
779         return 0;
780 }
781
782 static int raw3215_pm_start(struct ccw_device *cdev)
783 {
784         struct raw3215_info *raw;
785         unsigned long flags;
786
787         /* Allow I/O again and flush output buffer. */
788         raw = dev_get_drvdata(&cdev->dev);
789         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
790         raw->port.flags &= ~ASYNC_SUSPENDED;
791         raw->flags |= RAW3215_FLUSHING;
792         raw3215_try_io(raw);
793         raw->flags &= ~RAW3215_FLUSHING;
794         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
795         return 0;
796 }
797
798 static struct ccw_device_id raw3215_id[] = {
799         { CCW_DEVICE(0x3215, 0) },
800         { /* end of list */ },
801 };
802
803 static struct ccw_driver raw3215_ccw_driver = {
804         .driver = {
805                 .name   = "3215",
806                 .owner  = THIS_MODULE,
807         },
808         .ids            = raw3215_id,
809         .probe          = &raw3215_probe,
810         .remove         = &raw3215_remove,
811         .set_online     = &raw3215_set_online,
812         .set_offline    = &raw3215_set_offline,
813         .freeze         = &raw3215_pm_stop,
814         .thaw           = &raw3215_pm_start,
815         .restore        = &raw3215_pm_start,
816         .int_class      = IRQIO_C15,
817 };
818
819 #ifdef CONFIG_TN3215_CONSOLE
820 /*
821  * Write a string to the 3215 console
822  */
823 static void con3215_write(struct console *co, const char *str,
824                           unsigned int count)
825 {
826         struct raw3215_info *raw;
827         int i;
828
829         if (count <= 0)
830                 return;
831         raw = raw3215[0];       /* console 3215 is the first one */
832         while (count > 0) {
833                 for (i = 0; i < count; i++)
834                         if (str[i] == '\t' || str[i] == '\n')
835                                 break;
836                 raw3215_write(raw, str, i);
837                 count -= i;
838                 str += i;
839                 if (count > 0) {
840                         raw3215_putchar(raw, *str);
841                         count--;
842                         str++;
843                 }
844         }
845 }
846
847 static struct tty_driver *con3215_device(struct console *c, int *index)
848 {
849         *index = c->index;
850         return tty3215_driver;
851 }
852
853 /*
854  * panic() calls con3215_flush through a panic_notifier
855  * before the system enters a disabled, endless loop.
856  */
857 static void con3215_flush(void)
858 {
859         struct raw3215_info *raw;
860         unsigned long flags;
861
862         raw = raw3215[0];  /* console 3215 is the first one */
863         if (raw->port.flags & ASYNC_SUSPENDED)
864                 /* The console is still frozen for suspend. */
865                 if (ccw_device_force_console(raw->cdev))
866                         /* Forcing didn't work, no panic message .. */
867                         return;
868         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
869         raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
870         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
871 }
872
873 static int con3215_notify(struct notifier_block *self,
874                           unsigned long event, void *data)
875 {
876         con3215_flush();
877         return NOTIFY_OK;
878 }
879
880 static struct notifier_block on_panic_nb = {
881         .notifier_call = con3215_notify,
882         .priority = 0,
883 };
884
885 static struct notifier_block on_reboot_nb = {
886         .notifier_call = con3215_notify,
887         .priority = 0,
888 };
889
890 /*
891  *  The console structure for the 3215 console
892  */
893 static struct console con3215 = {
894         .name    = "ttyS",
895         .write   = con3215_write,
896         .device  = con3215_device,
897         .flags   = CON_PRINTBUFFER,
898 };
899
900 /*
901  * 3215 console initialization code called from console_init().
902  */
903 static int __init con3215_init(void)
904 {
905         struct ccw_device *cdev;
906         struct raw3215_info *raw;
907         struct raw3215_req *req;
908         int i;
909
910         /* Check if 3215 is to be the console */
911         if (!CONSOLE_IS_3215)
912                 return -ENODEV;
913
914         /* Set the console mode for VM */
915         if (MACHINE_IS_VM) {
916                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
917                 cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
918         }
919
920         /* allocate 3215 request structures */
921         raw3215_freelist = NULL;
922         spin_lock_init(&raw3215_freelist_lock);
923         for (i = 0; i < NR_3215_REQ; i++) {
924                 req = kzalloc(sizeof(struct raw3215_req), GFP_KERNEL | GFP_DMA);
925                 req->next = raw3215_freelist;
926                 raw3215_freelist = req;
927         }
928
929         cdev = ccw_device_create_console(&raw3215_ccw_driver);
930         if (IS_ERR(cdev))
931                 return -ENODEV;
932
933         raw3215[0] = raw = raw3215_alloc_info();
934         raw->cdev = cdev;
935         dev_set_drvdata(&cdev->dev, raw);
936         cdev->handler = raw3215_irq;
937
938         raw->flags |= RAW3215_FIXED;
939         if (ccw_device_enable_console(cdev)) {
940                 ccw_device_destroy_console(cdev);
941                 raw3215_free_info(raw);
942                 raw3215[0] = NULL;
943                 return -ENODEV;
944         }
945
946         /* Request the console irq */
947         if (raw3215_startup(raw) != 0) {
948                 raw3215_free_info(raw);
949                 raw3215[0] = NULL;
950                 return -ENODEV;
951         }
952         atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
953         register_reboot_notifier(&on_reboot_nb);
954         register_console(&con3215);
955         return 0;
956 }
957 console_initcall(con3215_init);
958 #endif
959
960 static int tty3215_install(struct tty_driver *driver, struct tty_struct *tty)
961 {
962         struct raw3215_info *raw;
963
964         raw = raw3215[tty->index];
965         if (raw == NULL)
966                 return -ENODEV;
967
968         tty->driver_data = raw;
969
970         return tty_port_install(&raw->port, driver, tty);
971 }
972
973 /*
974  * tty3215_open
975  *
976  * This routine is called whenever a 3215 tty is opened.
977  */
978 static int tty3215_open(struct tty_struct *tty, struct file * filp)
979 {
980         struct raw3215_info *raw = tty->driver_data;
981         int retval;
982
983         tty_port_tty_set(&raw->port, tty);
984
985         raw->port.low_latency = 0; /* don't use bottom half for pushing chars */
986         /*
987          * Start up 3215 device
988          */
989         retval = raw3215_startup(raw);
990         if (retval)
991                 return retval;
992
993         return 0;
994 }
995
996 /*
997  * tty3215_close()
998  *
999  * This routine is called when the 3215 tty is closed. We wait
1000  * for the remaining request to be completed. Then we clean up.
1001  */
1002 static void tty3215_close(struct tty_struct *tty, struct file * filp)
1003 {
1004         struct raw3215_info *raw;
1005
1006         raw = (struct raw3215_info *) tty->driver_data;
1007         if (raw == NULL || tty->count > 1)
1008                 return;
1009         tty->closing = 1;
1010         /* Shutdown the terminal */
1011         raw3215_shutdown(raw);
1012         tasklet_kill(&raw->tlet);
1013         tty->closing = 0;
1014         tty_port_tty_set(&raw->port, NULL);
1015 }
1016
1017 /*
1018  * Returns the amount of free space in the output buffer.
1019  */
1020 static int tty3215_write_room(struct tty_struct *tty)
1021 {
1022         struct raw3215_info *raw;
1023
1024         raw = (struct raw3215_info *) tty->driver_data;
1025
1026         /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */
1027         if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0)
1028                 return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE;
1029         else
1030                 return 0;
1031 }
1032
1033 /*
1034  * String write routine for 3215 ttys
1035  */
1036 static int tty3215_write(struct tty_struct * tty,
1037                          const unsigned char *buf, int count)
1038 {
1039         struct raw3215_info *raw;
1040         int i, written;
1041
1042         if (!tty)
1043                 return 0;
1044         raw = (struct raw3215_info *) tty->driver_data;
1045         written = count;
1046         while (count > 0) {
1047                 for (i = 0; i < count; i++)
1048                         if (buf[i] == '\t' || buf[i] == '\n')
1049                                 break;
1050                 raw3215_write(raw, buf, i);
1051                 count -= i;
1052                 buf += i;
1053                 if (count > 0) {
1054                         raw3215_putchar(raw, *buf);
1055                         count--;
1056                         buf++;
1057                 }
1058         }
1059         return written;
1060 }
1061
1062 /*
1063  * Put character routine for 3215 ttys
1064  */
1065 static int tty3215_put_char(struct tty_struct *tty, unsigned char ch)
1066 {
1067         struct raw3215_info *raw;
1068
1069         if (!tty)
1070                 return 0;
1071         raw = (struct raw3215_info *) tty->driver_data;
1072         raw3215_putchar(raw, ch);
1073         return 1;
1074 }
1075
1076 static void tty3215_flush_chars(struct tty_struct *tty)
1077 {
1078 }
1079
1080 /*
1081  * Returns the number of characters in the output buffer
1082  */
1083 static int tty3215_chars_in_buffer(struct tty_struct *tty)
1084 {
1085         struct raw3215_info *raw;
1086
1087         raw = (struct raw3215_info *) tty->driver_data;
1088         return raw->count;
1089 }
1090
1091 static void tty3215_flush_buffer(struct tty_struct *tty)
1092 {
1093         struct raw3215_info *raw;
1094
1095         raw = (struct raw3215_info *) tty->driver_data;
1096         raw3215_flush_buffer(raw);
1097         tty_wakeup(tty);
1098 }
1099
1100 /*
1101  * Disable reading from a 3215 tty
1102  */
1103 static void tty3215_throttle(struct tty_struct * tty)
1104 {
1105         struct raw3215_info *raw;
1106
1107         raw = (struct raw3215_info *) tty->driver_data;
1108         raw->flags |= RAW3215_THROTTLED;
1109 }
1110
1111 /*
1112  * Enable reading from a 3215 tty
1113  */
1114 static void tty3215_unthrottle(struct tty_struct * tty)
1115 {
1116         struct raw3215_info *raw;
1117         unsigned long flags;
1118
1119         raw = (struct raw3215_info *) tty->driver_data;
1120         if (raw->flags & RAW3215_THROTTLED) {
1121                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1122                 raw->flags &= ~RAW3215_THROTTLED;
1123                 raw3215_try_io(raw);
1124                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1125         }
1126 }
1127
1128 /*
1129  * Disable writing to a 3215 tty
1130  */
1131 static void tty3215_stop(struct tty_struct *tty)
1132 {
1133         struct raw3215_info *raw;
1134
1135         raw = (struct raw3215_info *) tty->driver_data;
1136         raw->flags |= RAW3215_STOPPED;
1137 }
1138
1139 /*
1140  * Enable writing to a 3215 tty
1141  */
1142 static void tty3215_start(struct tty_struct *tty)
1143 {
1144         struct raw3215_info *raw;
1145         unsigned long flags;
1146
1147         raw = (struct raw3215_info *) tty->driver_data;
1148         if (raw->flags & RAW3215_STOPPED) {
1149                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1150                 raw->flags &= ~RAW3215_STOPPED;
1151                 raw3215_try_io(raw);
1152                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1153         }
1154 }
1155
1156 static const struct tty_operations tty3215_ops = {
1157         .install = tty3215_install,
1158         .open = tty3215_open,
1159         .close = tty3215_close,
1160         .write = tty3215_write,
1161         .put_char = tty3215_put_char,
1162         .flush_chars = tty3215_flush_chars,
1163         .write_room = tty3215_write_room,
1164         .chars_in_buffer = tty3215_chars_in_buffer,
1165         .flush_buffer = tty3215_flush_buffer,
1166         .throttle = tty3215_throttle,
1167         .unthrottle = tty3215_unthrottle,
1168         .stop = tty3215_stop,
1169         .start = tty3215_start,
1170 };
1171
1172 /*
1173  * 3215 tty registration code called from tty_init().
1174  * Most kernel services (incl. kmalloc) are available at this poimt.
1175  */
1176 static int __init tty3215_init(void)
1177 {
1178         struct tty_driver *driver;
1179         int ret;
1180
1181         if (!CONSOLE_IS_3215)
1182                 return 0;
1183
1184         driver = alloc_tty_driver(NR_3215);
1185         if (!driver)
1186                 return -ENOMEM;
1187
1188         ret = ccw_driver_register(&raw3215_ccw_driver);
1189         if (ret) {
1190                 put_tty_driver(driver);
1191                 return ret;
1192         }
1193         /*
1194          * Initialize the tty_driver structure
1195          * Entries in tty3215_driver that are NOT initialized:
1196          * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
1197          */
1198
1199         driver->driver_name = "tty3215";
1200         driver->name = "ttyS";
1201         driver->major = TTY_MAJOR;
1202         driver->minor_start = 64;
1203         driver->type = TTY_DRIVER_TYPE_SYSTEM;
1204         driver->subtype = SYSTEM_TYPE_TTY;
1205         driver->init_termios = tty_std_termios;
1206         driver->init_termios.c_iflag = IGNBRK | IGNPAR;
1207         driver->init_termios.c_oflag = ONLCR;
1208         driver->init_termios.c_lflag = ISIG;
1209         driver->flags = TTY_DRIVER_REAL_RAW;
1210         tty_set_operations(driver, &tty3215_ops);
1211         ret = tty_register_driver(driver);
1212         if (ret) {
1213                 put_tty_driver(driver);
1214                 return ret;
1215         }
1216         tty3215_driver = driver;
1217         return 0;
1218 }
1219
1220 static void __exit tty3215_exit(void)
1221 {
1222         tty_unregister_driver(tty3215_driver);
1223         put_tty_driver(tty3215_driver);
1224         ccw_driver_unregister(&raw3215_ccw_driver);
1225 }
1226
1227 module_init(tty3215_init);
1228 module_exit(tty3215_exit);